Wear gloves. A net is very useful for capturing animals that will try to flee or fly.
Prepare a container
A shoebox with air holes in the lid, lined with a small cloth or paper towel works for most songbirds.
Put the bird in the box.
Cover the bird with a light cloth and gently put it in the box or crate.
Keep it warm
If the bird is cold, put one end of the shoebox on a towel over a heating pad set on low. You can also warm up a water bottle and wrap it with a towel to provide warmth. Make sure the bottle is secure and will not roll onto the animal.
If you can’t transport it immediately:
Keep the bird in a warm, dark, quiet place.
Do not give it food or water. Feeding an animal an incorrect diet can result in injury or death. Also, a captured animal will get food and water stuck in its fur/feathers potentially leading to discomfort and hypothermia.
Do not handle it. Leave the animal alone. Remember human noise, touch and eye contact are very stressful to wild animals.